Terrorism: Medical Countermeasures

by Food and Drug Administration (FDA)

(Page 3 of 4)

Ensuring that safe and effective medical products are available for diagnosing, treating, and preventing illness due to terrorist agents is the responsibility of the FDA's Center for Drug Evaluation and Research, the Center for Devices and Radiological Health, and the Center for Biologics Evaluation and Research. Biologics are medical products derived from living sources. These products include vaccines, blood and blood derivatives, and cells and tissues for transplantation.

The FDA works with other health agencies and manufacturers to identify promising research and to encourage the development of new products. The FDA supports clinical research to find out whether products approved for one indication could be used for an indication related to counterterrorism. In some cases, the FDA conducts research on its own.

Under a new regulation known as "the animal efficacy rule," the FDA can approve medical treatments against terrorist agents based on effectiveness data from animal studies when human studies are unethical and not feasible. Studies demonstrating the safety of the new product in humans are still required.

The FDA also publishes guidance for using medical countermeasures in special groups such as the first responders in an emergency, people in the military, people who live near nuclear facilities, pregnant women, children, and people with compromised immune systems.

As part of national policy, the FDA places high priority on Category A agents, a designation the CDC gives to the greatest threats to public health. Category A agents include the organisms that cause anthrax, plague, smallpox, tularemia and viral hemorrhagic fevers, as well as botulinum toxin. Here are some examples of areas in which the FDA works on medical countermeasures:

Anthrax: Anthrax is an infectious disease caused by the spore-forming bacterium Bacillus anthracis. There are three forms of anthrax infection: skin (cutaneous), gastrointestinal, and inhalational.

Cutaneous anthrax can be acquired when spores enter cuts or abrasions in the skin. It is marked by a sore that progresses from a red raised area on the skin to an ulcer with a black center. Gastrointestinal anthrax can result from ingesting food that contains B. anthracis spores. It can cause fever, loss of appetite, nausea, and vomiting, which can progress to vomiting of blood and severe, often bloody, diarrhea and abdominal pain.

Inhalational anthrax, which is associated with the highest death rates, occurs when spores are inhaled and cause infection in the lungs. Initial symptoms are similar to a cold or the flu, but the illness worsens over several days and a high fever typically develops.

The treatment for all types of anthrax is antibiotics. The antibiotics approved by the FDA are Cipro (ciprofloxacin), drugs in the tetracycline class such as doxycycline, and some drugs in the penicillin class such as procaine penicillin G.

The anthrax vaccine is primarily given to people in the military and is only recommended for individuals considered to be at high risk, such as scientists who handle anthrax bacteria in a research lab. During the anthrax attacks in 2001, the FDA made one type of anthrax vaccine, Anthrax Vaccine Adsorbed, available under an investigational new drug application (IND) for people who are not in the military and who had been exposed to inhalational anthrax. An IND allows a treatment to be made available before final FDA approval of the drug. These individuals also received antibiotics.

The FDA is part of an interagency working group, together with NIH, CDC, DoD, and HHS, that is focused on encouraging the development of new generation recombinant anthrax vaccines intended to prevent inhalational anthrax both before and after exposure.

The genetic makeup of anthrax is being studied to help improve vaccines and treatments. FDA scientists are studying a weakened infectious strain of bacteria as a possible carrier to stimulate antibodies against anthrax. They also are evaluating whether small, non-infective pieces of anthrax bacteria potentially could be used as safe and effective vaccines. The FDA and CDC are studying the possibility that anthrax immune globulin (AIG) may be useful in prevention or treatment of anthrax.

In August 2003, the agency granted fast-track designation to an IND for ABthrax, an antibody that is being evaluated for the prevention and treatment of anthrax infections. The FDA also issued guidance to the drug industry on developing antimicrobial drug products for inhalational anthrax. There is also research underway on an investigational device that tests for the presence of B. anthracis.

Smallpox: The last confirmed case of smallpox in the United States was in 1949, and the last naturally occurring case in the world was recorded in Somalia in 1977. The World Health Organization has declared the illness eradicated, but if one case were intentionally introduced, the result could be a public health emergency. Caused by the variola virus, smallpox is highly contagious and can be spread by close contact with a person who has smallpox symptoms — high fever, fatigue, headaches, backaches, vomiting, rash, and pus-filled blisters. There is no proven treatment. The death rate in the past was about 30 percent, and death rates can be higher for infants and young children.

Smallpox can be prevented through vaccination. Dryvax (smallpox vaccine, dried, calf lymph type), made by Wyeth Laboratories of Marietta, Pa., is the only smallpox vaccine currently licensed by the FDA. In October 2002, the FDA approved a license supplement for a 100-dose kit of Dryvax with a new supply of diluent, which is the liquid that's mixed with dried vaccine before it's administered. Before this supplement, Dryvax was only available for use in clinical investigations under an IND.

About the Author

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.